Question: If $x \veebar y = 2x-5y$ and $x \oplus y = 5y+3$, find $(5 \oplus 4) \veebar 6$.
First, find $5 \oplus 4$ $ 5 \oplus 4 = (5)(4)+3$ $ \hphantom{5 \oplus 4} = 23$ Now, find $23 \veebar 6$ $ 23 \veebar 6 = (2)(23)-(5)(6)$ $ \hphantom{23 \veebar 6} = 16$.